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Engine Torque Sensing Agriculture • Horticulture • forestry • Environment • Amenity Spring 2001 ENGINE TORQUE SENSING MANGO DESTONER _BS50 vl y y •V' J 1/? -mx i'i'taisi Lv. i h i for mew xamine trae MembeVwishing to submi^Epers or displa^Vosters Deadline i^paper shou^Pontact: •r St^m Parkin \\\>« Silso^Ksearch Institute * \ V k, ^ k . %. [email protected] ^ - V %< ^ *• / erence details coptact^The Secretariat, Institution of Ag St End Road, ledford. MK45 4D0, Tel: 01525 861096, Fax:/]1 525 i [email protected] -V / to: JD 3000 Series telescooic / Volume 56 No I, Spring 2001 The Journal for Professional Engineers in Agriculture, Forestry, Environment and Amenity LANDWARDS Editor Eur Ing Prof Brian D Witney PhD CEng FIMechE HonFIAgrEMemASAE LAND TECHNOLOGY LTD 33 South Barnton Ave, Edinburgh, EH4 6AN CONTENTS Tel/Fax: 0131 336 3129 E-mail: [email protected] Website: http://www.landtec.co.ul< Feature Articles Advertising 2 TRACTOR DESIGN All enquiries to the Institution of Engine torque sensing in farnn tractors Agricultural Engineers How it improves performance Tel: 01525 861096 Fax:OI525 861660 W John Foxwell Origination: David King 20 FOOD PROCESSING Mango destoner Printing: Barr Printers Ltd Federico Hahn Price £16.00 per copy 22 RURAL DEVELOPMENT subscription £52.00 (post free in UK) Research-development linkages, a case study from south east Publisher Zimbabwe Landwards is published quarterly by: Institution of Agricultural Engineers, Jim Ellis-Jones, Vurayai Zvarevashe, West End Road, Silsoe, Steve Twomlow and Kelly Stevenson Bedford, MK45 4DU Tel: 01525 861096 Fax: 01525 861660 News and Comment E-mail: [email protected] Website: http://www.iagre.org 12 News scan President 28 Company and product information Geoffrey J H Freedman BScCEng FIAgrE Chief Executive & Secretary Christopher RWhetnall Front cover: A^ossey Ferguson 8250 (photo:AGCO) lEngMlAgrEMemASAE The views and opinions expressed in individualcontributions are not those necessarily of the Institution or the Editor. Landwards is compiled from information received by the Institution of Agricultural Engineers but no responsibil ity can be accepted by the governing Council, the Publishers or the Editor in respect of any errors or omis sions. The Editor reserves the right to edit any material sent to the journal. Material from this publication may be quoted or reported on condition that full credit is given to Landwards and to the author, and that the date of publication and volume number are stated. In the interest of factual reporting, reference to trade names and proprietary products may be inevitable. No endorsement of the named products or manufacturers is intended and no adverse criticism is implied of similar products which are not mentioned. ©THE INSTITUTION OF AGRICULTURAL ENGINEERS ISSN 1363-8300 TRACTOR DESIGN A Ford 7000 torque controlling a mounted chisel plough fdro u. W John Foxwell ENGINE TORQUE SENSING How it improves performance Abstract pulling trailing implements. I he background of implement control is discussed from Ferguson's early attempts In a provisional patent to the latest torque sensing patents. The benefit of torque sensingover the linkage application dated February 12. sensingof mounted implements is clearly detailed,as are the benefits of applying 1925 entitled Apparatus for torque sensingto the control of trailed implements. As torque sensinggives the tractor Coupling Agricultural its own inbuilt dynamometer;torque sensing has other benefits such as diagnostic testing Implements to Tractors and to detect hidden engine problems. Itcould also be useful in determining the transmission Automatically Regulating the efficiency of tractors undergoing the OECD tests ifthe drawbar tests on the track were Depth of Cut inWork, he superseded by dynamometer tests measuringthe actual axle power. Characteristic wrote in one approach that: performance curves based on axle power with suggestions for predictingthe The torque reaction of the performance on various soils are also included. tractor may be utilisedfor controlling the depth of cut of the implement and. as this Background to I) in order to eliminate their reaction is dependent on the implement control depth wheels and transfer the draught of the implement, it is Seventy-iiveyears ago in implement weight to the immediately rectified and the Ireland, far sighted Harry drivingwheels ofthe tractor; normal depth of cut Ferguson experimented with so enabling the tractor to be constantly maintained'. He implements mounted to the lighter and more suggested that this might be rear of a Fordson tractor (Fig, manoeuvrable than tractors achieved by using the worm 2 lAHDWMDi SPRING 2001 In the amended complete influenced tractor design, specification of the patent, namely the development of however he did not mention the maize header on the torque sensing again,and he combine harvester and the eventually developed the chemical control ofweeds. three-point hitch, as we know These two factors eliminated it today, with top linksensing the need for the narrow of implement draught. In tricycle rowcrop tractors that 1938, he sold the idea to were standard in the'corn Henry Ford and, between belt', but below 40 kW in them, the 9N Ford Ferguson power because of the single Mr John Foxwell's technical tractor was introduced in front wheels. Wide front axles 1939, It was an immediate replaced the tricycle front education was obtained at the success, being small and light; axles and the size and power Merchant Venturers Technical College and when equipped with the of the tractors rapidly in Bristol and the SEETC in new rubber tyres, very increased together with the Barking, Essex. He won a Ford manoeuvrable, very safe and use of the three point hitch of scholarship in 1936 graduating top easy to drive. As the which there were three student in I9]9. During the war implements were mounted at categories in size. To handle he worked on the designs of the rear, in ideal soil conditions, the longer and heavier military trucks and personnel weight was transferred to the implements which did not carriers before being transferred to rear wheels from both the work well with the top link design implements lor (he new plough and the front axle by sensing,lower link'draft E27N tractor in 1944. He progressed to Executive Engineer - . t *• an amount approximately control'was invented. The equal to the amount of weight lines of pull of these heavier Tractors in I9SS and influenced transferred when the mounted implements passed the design of the Fordson Major implement is in the transport to the rear of the ball ends of and Dexta tractors. Transferred to position (Fig, 2a). up to almost the lower links, causing tension the U.S. in 1962,he became Chief twice that of the implement's rather than compression loads Engineer Ford Tractor Operations weight (Figs 2b & 2c). This was in the top link. (Worldwide] in 1964 and was reduced in harder soils and Some long multi-furrow responsible for the 2000,3000, when the line of pull became ploughs were semi-mounted 4000, SOOO, 7000,6000 and 9000 parallel to the ground no on the tractor and attached range of tractors. In 1975 he weight was transferred. Later only to the two lower links. retired to form his own consulting pinion in the rear axle of the as Ferguson's patents expired The three-point hitch has a self company. Now fully retired he tractor Quoting again from other manufacturers adopted correcting built-in feature keeps up to date with tractor the application, he states:'The the three-point hitch. which keeps the corrections affairs, fie is a 40 year Fellow of worm is capable of endwise smallwhen hard ground is the lAgrE and a S5 year Fellow of movement and an extension Other influences tilled. When the lower links the IMechE as well as being a thereof is arranged in contact In the late nineteen fifties, two alone were used, it needed an member of the SAE. He keeps fit with an arm of a bell-crank other events in the US additional manual control by playing golf twice a week in lever pivoted on the tractor Kichigan and in Florida in the and used for suspending the implement from the tractor through suitable linkage. Thus, the load or end thrust on the worm is proportioned to the Ipp—lf draught of the implement and any variation in the draught will produce a corresponding variation in the load, or end thrust, with the result that the extension ofthe worm in contact with the ball-crank t vmi • 1* lever will pivot the same either upwards or downwards, as the case might be, to raise or lower the depth of cut of the Fig. I. The integral construction of the 1917 Fordson model was implement according to a factor in making it the first tractor to be mass produced; the whether the depth of cut of initial 5000 were shipped to Britain in 1917; in 1919, production the implement is to be was shifted to Cork in Ireland and in 1932, to Dagenham; note reduced or increased'. the worm drive in the rear axle. [Source; British patent no. 253,566 dated February 12, 1925 by Harry Ferguson]. TRACTOR DESIGN which the operator could the wheelslip approaches 25%. factor into minimise the large only a small increase in corrections which occur in drawbar pull will induce hard ground. complete wheelspin, A further factor that particularly on the harder facilitated the increase in surfaces. A further useful chart tractor size and power was the (Fig. 3c) also shows the effect improvement inthe hydraulic of tractor speed on soil systems applied to the control ploughing resistance. of pulltype equipment which C"G could not be mounted on the Three point hitch three point hitch. Higher sensing problems 085L operating pressures, coupled While the adoption of the with the standardisation of three point hitch with linkage remote hydraulic cylinders and control of an implement was a improved breakaway hose monumental step forward, couplers enabled one linkage control of an operator to hitch and operate implement has one very great extremely large and heavy disadvantage, namely that it pieces of equipment maintains the same selected draught of the implement at all Predicting times.
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